Uterine leiomyoma/leiomyomata (uterine fibroid disease) is a clinical problem that goes under a variety of names, including uterine fibrosis, uterine hypertrophy, uterine leiomyomata, myometrial hypertrophy, fibrosis uteri, and fibrotic metritis. Essentially, uterine fibrosis is a condition where there is an inappropriate deposition of fibroid tissue on the wall of the uterus. This condition is a cause of dysmenorrhea and infertility in women.
Endometriosis is a condition of severe dysmenorrhea, which is accompanied by severe pain, bleeding into the endometrial masses or peritoneal cavity and often leads to infertility. The symptoms' cause appears to be ectopic endometrial growths that respond inappropriately to normal hormonal control and are located in inappropriate tissues. Because of the inappropriate locations for endometrial growth, the tissue seems to initiate local inflammatory-like responses causing macrophage infiltration and a cascade of events leading to initiation of the painful response. Evidence suggests that a cause of uterine fibrosis and endometriosis is an inappropriate response of fibroid tissue and/or endometrial tissue to estrogen.
Many publications have appeared within the last ten years disclosing selective estrogen receptor modulators (SERMs), e.g., U.S. Pat. Nos. 5,484,795, 5,484,798, 5,510,358, 5,998,401 and WO 96/09040. Many of these SERMs, generally speaking, have been found to have a beneficial estrogen agonist activity in the bone and cardiovascular systems with a concomitant beneficial estrogen antagonist activity in the breast. A small, particularly useful subset of such compounds has also been found to have an estrogen antagonist effect in the uterus. A compound with this SERM profile holds particular promise in treating uterine fibroid disease and/or endometriosis.
However, the clinical use of such SERM compounds for the treatment of uterine fibroid disease and/or endometriosis, particularly in pre-menopausal women, has been hampered by the propensity of said compounds to have significant ovarian stimulatory effects. A great need currently exists, therefore, for new SERM compounds that behave as estrogen antagonists in the uterus that do not significantly stimulate the ovaries.